High-Dose Prenatal Vitamin D and Childhood Atopy: Why Maternal Smoking History Matters

Introduction: The Intersection of Nutrition and Environment in Early Atopy

The rising prevalence of atopic diseases, including atopic dermatitis, asthma, and allergic rhinitis, represents a significant global health burden. Atopic dermatitis (AD), often the first step in the so-called atopic march, frequently manifests in early infancy and significantly impacts the quality of life for both children and their families. While genetic predisposition is a known factor, the rapid increase in incidence suggests a critical role for environmental and nutritional modifiers during the prenatal and early postnatal periods. Among these, vitamin D has emerged as a key candidate for intervention due to its profound immunomodulatory effects. Recent evidence, however, suggests that the efficacy of vitamin D supplementation may not be uniform across the population but rather modified by environmental factors, most notably maternal tobacco exposure.

The COPSAC2010 Trial: High-Dose Supplementation and the Cotinine Modifier